Moral brains - the neuroscience of morality - Prinz 2016
33 pág.

Moral brains - the neuroscience of morality - Prinz 2016


Disciplina<strong>psicologia Cognitiva</strong>141 materiais122 seguidores
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Moral Brains
T H E N EU R O S C I EN C E O F M O R A L I T Y
Edited by S. Matthew Liao
 
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Sentimentalism and the Moral Brain
Jesse Prinz
Over the last dozen years, there has been enormous interest in studying the neural 
basis of moral judgment. A growing number of researchers believe that the moral brain 
will lead to insights about the nature of morality. There is an emerging conviction that 
long- standing debates in psychology and philosophy can be settled, or at least propelled 
forward, by neuroscience. Much of this conviction centers around the more specific 
belief that we can make progress on questions about the relationship between moral 
judgment and emotion. That confidence, however, rests on undue faith in what brain 
scans can reveal, independent of other sources of evidence, including both behavioral 
studies and theoretical considerations. When taken on their own, extant neuroimag-
ing studies leave classic debates unsettled, and require other evidence for interpretation. 
This suggests that, at present, the idea that neuroscience can settle psychological and 
philosophical debates about moral judgments may have things backward. Instead, psy-
chological and philosophical debates about moral judgment may be needed to settle the 
meaning of brain scans. This reversal of directionality does not render brain scans unin-
teresting. The surprising range of hotspots seen in studies of moral judgment need to be 
decoded. Once decoded in light of other evidence, neuroimaging results can be helpful 
and informative.
My goal here will be, first, to establish that neuroimaging studies leave much uncer-
tainty about moral judgment and, in particular, about the relationship between moral-
ity and emotion. Fortunately, I will argue, behavioral evidence and philosophical argu-
mentation can help settle the questions that scans leave unanswered. This, then, points 
toward an account of what different brain structures are contributing to moral cogni-
tion. Such a mapping can be useful in making progress in this domain.
To spoil the surprise, I will say at the outset that I interpret the preponderance of em-
pirical evidence as supporting a fairly traditional kind of sentimentalist theory of moral 
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46 Emotions versus Reason
judgment. According to this theory, occurrent moral judgments are constituted by emo-
tional states. I  will contrast this theory with a range of alternatives and argue for its 
explanatory superiority. For those who are unconvinced by my arguments, the chapter 
can be read as a plea for an integrative methodology, and many claims can be accepted 
without joining my sentimentalist bandwagon. For those less interested in methodol-
ogy, the chapter can be read as a defense of sentimentalism, which happens to engage 
neuroscientific research.
1.1. Blinded by Head Lights: The Ambiguity of Imagining
1.1.1. The Anatomy of Mor alit y
Since Greene et al.\u2019s seminal (2001) study of moral dilemmas, there have been numerous 
efforts to identify brain structures involved in moral judgments. Though there is a fair 
degree of convergence between these studies, the results are often somewhat bewildering. 
Even within a single study, a variety of brain structures are usually implicated, and it is 
often far from obvious how to interpret the results. I will not attempt a complete review 
here. A survey of some of the main findings will suffice to make the point. I will focus 
on studies that compare moral judgments to nonmoral judgments, though I should men-
tion at the outset that many studies also compare different kinds of moral judgments, 
and many published reports include both kinds of comparisons. There will be occasion 
to discuss differing kinds of moral judgments as we move on in the discussion.
Let\u2019s begin with Greene et al. (2001). Though their emphasis lies elsewhere, they do 
compare moral judgments (i.e., choices about the right thing to do in a moral dilemma) 
with nonmoral judgments (e.g., dilemmas about whether to replace an old TV set or 
whether to take a bus or a train). The findings suggest that moral dilemmas recruit the 
following brain structures to a greater degree than nonmoral dilemmas: medial frontal 
gyrus (including parts of Brodmann areas 9 and 10; the latter is also known as ventrome-
dial prefrontal cortex, or VMPFC), posterior cingulate (BA 31), and the angular gyrus 
(BA 39) bilaterally. Greene et al. also note increased activation in the superior parietal 
lobule (BA 7/ 40), but say little about that in their discussion.
Another seminal study, by Moll et al. (2001), compared judgments of moral wrong-
ness (e.g., \u201cThey hanged an innocent person\u201d) to judgments of factual wrongness (e.g., 
\u201cStones are made of water\u201d). Moral judgments were associated with activity in medial 
frontal gyrus (BA 9/ 10), as Greene et al. found, as well as the right angular gyrus (con-
sistent with Greene, but more lateralized). They also report activity in the left precuneus 
(BA 7, just above the posterior cingulate), the right temporal pole (BA 38), and the right 
posterior superior temporal sulcus (STS). One year later, Moll, Oliveira- Souza, Bramati, 
et al. (2002) published a study using a similar design and reported slightly different, but 
overlapping results. As compared to neutral sentences, moral sentences were associated 
with increases in parts of the left medial temporal gyrus (BA 10), as well as adjacent 
medial orbital frontal cortex (OFC, or BA 11).
 
 
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Sentimentalism and the Moral Brain 47
In another study, Moll, Oliveira- Souza, Eslinger, et al. (2002) presented participants 
with photographs depicting morally bad behavior. As compared to neutral images, the 
moral photos were associated with medial frontal and orbital frontal areas again (BA 9/ 
10/ 11), precuneus, and the STS (including parts of BA 21 and 38), all in the right hemi-
sphere. There was also bilateral activity in middle temporal gyrus (BA 19/ 22), as well as 
increases in the amygdala and the midbrain. BA 22 is adjacent to the angular gyrus (BA 
39) and portions of the superior parietal lobule (BA 40). The area encompassing all three 
is sometimes called the temporal partial junction.
Other pioneering results include Heekeren et  al.\u2019s (2001) study, which compares 
morally anomalous to semantically anomalous sentences. The moral condition was as-
sociated with activity in the left angular gyrus (BA 39), the left middle temporal gyrus 
(BA 22), and the temporal pole (BA 38), consistent with other studies, and beyond these 
structures, bilateral inferior frontal gyrus (BA 45/ 47), which may reflect the linguistic 
nature of their task. In a subsequent study with a similar design, Heekeren et al. (2003) 
found that moral sentences were associated with area 47 again (perhaps a language area), 
as well as cast of areas familiar from the other moral judgment studies: medial frontal 
gyrus, STS, and temporal pole.
I will mention work by just one other research group; other findings follow a similar 
pattern. In one study, Harenski and Hamann (2006) presented participants with morally 
charged pictures (as in Moll, Oliveira- Souza, Eslinger, et al. 2002) and compared these to 
either nonmoral emotional pictures or a neutral baseline (deciding whether numbers are odd 
or even). When compared to the neutral condition, moral images produced greater activa-
tion in right medial frontal gyrus (BA 10), left amygdala, and left superior frontal gyrus. The 
latter area\u2014 not a big player in other studies\u2014 is associated with executive working memory 
spatial cognition; this may simply reflect that the neutral condition (classifying odd- even 
numbers) is highly automatic and nonspatial compared to picture viewing. As compared to 
nonmoral pictures,